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In this dichotomous study, the silicone-based softeners were produced with the contribution of some additives such as glycerin, polyethylene glycol 400 (PEG 400) and polyethylene glycol 4000 (PEG 4000) which had hydrophilic hydroxyl groups for providing or developing the hydrophilic character, lubricity and filling properties of the emulsions. The paper aims to discuss this issue.

The produced softeners were applied to the 100 percent cotton-knitted fabrics at different concentrations (owf%). In the first part of the study, the produced silicone emulsions were characterized via particle size, polydispersity index (PDI), zeta potential and TGA analyses. In addition, the effects of these emulsions on the mechanical properties of the fabrics were examined by bursting strength and pilling tests, and also the whiteness degrees (Berger value) of fabrics were researched. In the second part of the study, the effects of produced silicone softeners on the comfort properties of the fabrics were investigated.

According to the results, it was possible to say that the additives could be successfully added to the silicone emulsions, and they did not have a crucial effect on the properties of the emulsions or the mechanical and whiteness properties of the fabrics.

In this study, the additives were used as single form in the softeners recipes; however, their dual or trio combinations and/or their different concentrations could be used in the softeners emulsions.

In order to enhance the hydrophilic character, the lubricity and filling properties of the silicone softeners, they could be produced by using appropriate additives.

The contribution of the additives to the recipes of the silicone softeners is a novel approach.

In this study, which is divided into two parts, the silicone softeners having different properties and including different additives as glycerin, polyethylene glycol 400 (PEG 400) and polyethylene glycol 4000 (PEG 4000) (due to their high hydrophilic characters) are produced for the purpose of providing or developing the hydrophilic character, lubricity and filling properties of the emulsions. The paper aims to discuss this issue.

In the first part of the study, the produced silicone emulsions were characterized and applied to the 100 percent cotton-knitted fabrics. In addition, the mechanical properties and whiteness degrees of the fabrics were also researched. In this part of the study, the effects of the produced silicone softeners on the comfort properties of the fabric samples were investigated by qualitative handle, hydrophility, contact angle, air permeability, thermal comfort and moisture management tests.

The results showed that while classic silicone application improved mechanical comfort properties of the samples such as the handle and drape properties, they worsened other thermal comfort properties as hydrophility, transfer or dispersion of the moisture, and air permeability. In addition, the thermal comfort properties about heat transfer of the fabric samples were not significantly affected by application of the silicone softeners. All results were affected from the producing recipe of the silicone softeners, and generally the usage of the additives had positive effect on the comfort results depending on the producing recipe (especially type of the silicone oil) of the silicone softeners.

In this study, the additives were used in single form; however, their dual or trio combinations and/or their different amounts can be used in the emulsions.

In order to enhance the hydrophilic character, lubricity and filling properties of the silicone softeners, they could be produced by using appropriate additives.

In the literature, there were not any studies about the silicone softeners including different additives. So the authors can say that the contribution of the additives to the recipes of the silicone softeners is a novel approach.

ALTHOUGH the element silicon is second only to oxygen in order of abundance in the earth's crust the chemistry of its compounds and in particular of organo‐silicon compounds had developed but little before the turn of the century. It is true that the German chemist Friedel and his students Crafts and Ladenburg and later Polis prepared a few isolated organo‐silicon compounds during the latter half of the nineteenth century (1863–1886), but the land mark in this field is undoubtedly the classical work of Professor F. S. Kipping and his school at University College, Nottingham. This work extended over nearly forty years from 1899 to 1937 during which time a systematic study was made of this branch of chemistry.

The purpose of this study is to determine required paint and silicone proportions, their mixing rate and duration to eliminate the pattern problems caused by the misuse of silicone polymers in hammertone paints. Results of the findings aim at preventing raw material, manufacturing time and labour losses in hammertone paint production.

A paint formulation produced commercially was used. The effects of silicone proportion and mixing rate and paint and pigment density on the pattern formation within the paints, to which the spray painting method was applied, were investigated. Brightness controls of the produced paints were done, and the effect of the additive polymer on brightness was investigated. Photographs of paints for each practice were taken.

The most suitable silicone proportion and mixing conditions for the silver grey paints, in which Al non-leafing pigments were used, were calculated as 0.034-0.036 g/kg-paint and 15 s at 200 rpm, respectively. It was observed that the increase in pigment density increased required silicone proportion for the desired pattern. It was determined that mixing rate and duration were very significant in pattern formation, and that silicone decomposed and the pattern was disrupted in long-continued mixings. In addition, excess silicone use disrupted the pattern and decreased the paint brightness.

This research was conducted for hammertone paints, which are industrial and self-patterned aluminium silvered decorative paints. The results can be used for hammertone paint production.

The results will enable manufacturers to produce hammertone paints more economically. Results can be used in the paint industry to produce such paint.

It is crucial to produce high-quality products using less raw materials in today’s industry, where the amount of raw materials is decreasing, and economical and reliable production is becoming increasingly important. When environmental impacts in the solvent-based paint industry are taken into consideration, paint production in shorter times is important for both workers’ and environmental health. As a result of this study, hammertone paints will be produced more economically by appropriate production conditions yet without any energy, raw material and time loss.

The effects of space environment on friction and wear and on the selection of lubricants and self‐lubricating materials for spacecraft mechanisms are discussed, with special emphasis on the ultrahigh vacuum of space. Experimental studies have demonstrated the feasibility of using selected oils and greases to lubricate lightly loaded ball bearings without replenishment for periods of over one year under the following conditions of operation : speeds of 8,000 rpm, temperatures of 160 to 200°F., and vacuum of 10–8 torr. Over one‐half year of successful operation has been achieved under similar operating conditions with self‐lubricating retainers of reinforced Teflon, provided that the loads were light. Bonded films of molybdenum disulfide have given shorter lifetimes and poor repro‐ducibility. Metal‐to‐metal slip‐ring contacts introduce excessive electrical noise into circuits when operated in vacuum of 10–7 torr. The noise (as well as the friction and wear) can be markedly reduced by providing a small amount of oil vapor, sufficient to maintain a pressure on the order of 10–6 torr, or by incorporating molybdenum disulfide into the brush material.

The performance of oil-filled pressure cores is very much affected by the corrugated diaphragm and the oil filling volume. The purpose of this paper is to show the effects of different corrugated diaphragms, different oil filling volumes and different treatments of the corrugated diaphragms on the performance of pressure sensors.

Pressure-sensitive cores with different diaphragm diameters, different diaphragm ripple numbers and different oil filling volumes are produced, and thermal cycling is introduced to improve the diaphragm performance, and finally the performance of each pressure-sensitive core is tested and the test data are analyzed and compared.

The experimental results show that the larger the diameter of the corrugated diaphragm used for encapsulation, the better the performance. For pressure-sensitive cores using smaller diameter corrugated diaphragms, the performance of one corrugation is better than that of two corrugations. When the number of corrugations and the diameter are the same size, the performance of the outer ring of the diaphragm with concave corrugations is better than that with convex corrugations. At the same time, the diaphragm after thermal cycling treatment and appropriate reduction of encapsulated oil filling can improve the performance of the pressure-sensitive core.

By exploring the effects of corrugated diaphragm and oil filling volume on the performance of oil-filled pressure cores, the design of oil-filled pressure sensors can be guided to improve sensor performance.

THE above two‐day symposium sponsored by the Tribology Group of the Institution of Mechanical Engineers and held at their h.q. in London from the 19th‐20th February, clearly demonstrated that grease is an engineering component and needs as much attention in selection and application as might be given to the design of the component that it lubricates.

A PAPER presented to the National Lubricating Grease Institute at Philadelphia in October 1971, by W. H. Chappell and J. R. Soulen (Pennwalt Corporation) gave details of laboratory test results of behaviour of a new complex sulphide, arsenic thioantimonate, AsSbS4(ATA). This product provided excellent E.P. and anti‐wear properties in mineral oil, ester, and silicone base fluids with both soap and clay type thickeners.

As a result of the revisions at present being made to the science syllabus for schools, a large number of teachers in grammar and secondary modern schools are finding themselves involved for the first time in the mysteries of high vacuum. This article is intended as a guide to the practical aspects of obtaining and demonstrating high vacuum in schools. It contains a brief description of the workings of modern high vacuum pumps and gauges, together with some elementary ‘dos and don'ts’ of vacuum technique.